2型糖尿病微血管病变患者血浆同型半胱氨酸的变化及其机制的探讨

目的 了解血浆同型半胱氨酸（Hcy)与2型糖尿病微血管病变（DMAP）间的关系，并分析影响糖尿病（DM）患者Hcy代谢的因素。方法 157例DM患者分为三组：无微血管并发症组（NDC）、糖尿病视网膜病变组（DR）和糖尿病肾病（DN）组；正常对照组（CON）组28例。测定血浆Hcy、叶酸、维生素B12浓度，并以PCR－RFLP技术检测亚甲基四氢叶酸还原酶（MTHFR）C667T突变和蛋氨酸合成酶还原酶（MSR）A66G突变率。结果 DM各组血Hcy浓度及空腹高Hcy血症发生率高于CON组，DN组又高于NDC组（P＜0．05）。DM患者血Hcy浓度与MTHFR BB基因型、BMI、HbAlc、FBG、PBG、二甲双胍的使用呈正相关，与血浆叶酸和VitB12呈明显负相关，与MSR基因型无关。多元逐渐回归分析结果显示，VitB12、HbA1c、MTHFR基因型和叶酸是DM患者血Hcy浓度的影响因素。结论 空腹高Hcy因症是DMAP的危险因子；2型DM中MTHFR基因型、VitB12、叶酸以及代谢紊乱的程度影响Hcy的浓度。     

Increased plasma adiponectin concentrations are associated with microangiopathy in type 1 diabetic subjects

Aims/hypothesis Insulin resistance is related to an increased risk of diabetic retinopathy and nephropathy in type 1 diabetes. Patients with insulin resistance and/or macrovascular disease have abnormally low levels of adiponectin. The aim of this study was to investigate the relationships between adiponectin and renal and retinal diabetic complications in type 1 diabetic patients.Methods In this 6-year prospective follow-up observational study, we evaluated the severity of retinopathy at baseline and determined the incident risk of microalbuminuria in 126 normoalbuminuric patients with type 1 diabetes. Each patient was age- and sex-matched to two non-diabetic control subjects.Results Plasma adiponectin concentrations were significantly higher in diabetic subjects than in control subjects (p<0.0001). The adiponectin concentration was significantly higher in patients with severe diabetic retinopathy than in those without (39.1±14.0 vs 29.0±13.0 g/ml, p=0.0005). The 18 patients who developed persistent microalbuminuria had higher adiponectin concentrations than the other patients (35.8±14.5 vs 30.6±13.7 g/ml). Increased adiponectin concentrations were independently associated with the occurrence of microalbuminuria (p=0.0158) after adjustment for baseline urinary albumin concentration (p=0.004), sex (p=0.0054), blood pressure (NS) and metabolic control (NS).Conclusions/interpretation The elevated adiponectin concentrations observed in subjects with microvascular disease may indicate an altered regulation of this adipocytokine in patients with complications associated with type 1 diabetes.     

Autonomic neuropathy in Type 2 diabetic patients is associated with hyperinsulinaemia and hypertriglyceridaemia.

AIMS: To clarify whether parasympathetic neuropathy in Type 2 diabetic patients is associated with features of the insulin resistance syndrome. METHODS: Blood pressures, glycaemic control (HbA1c), plasma lipids, residual beta-cell function (fasting plasma C-peptide), autonomic nerve function, urinary albumin excretion and glomerular filtration rate (Cr-EDTA clearance) were evaluated in 82 Type 2 diabetic patients (age 63+/-years) 5 years after diagnosis of diabetes. RESULTS: Parasympathetic neuropathy (an abnormal age corrected E/I ratio) was found in 24/82 (29%) patients. After adjustment for body mass index (BMI), patients with parasympathetic neuropathy had elevated fasting plasma C-peptide (P < 0.001) and triglyceride (Tg) (P < 0.05) levels compared with patients without parasympathetic neuropathy. In addition, the age corrected E/I ratio correlated inversely with Tg (r=-0.31; P<0.01) and fasting plasma C-peptide (r=-0.32; P < 0.01) in the Type 2 diabetic patients. CONCLUSION: Autonomic neuropathy 5 years after diagnosis of Type 2 diabetes is associated with an unfavourable metabolic risk profile.     

Pioglitazone increases circulating adiponectin levels and subsequently reduces TNF-alpha levels in Type 2 diabetic patients: a randomized study.

BACKGROUND: Adipocytokines are involved in the development of insulin resistance and endothelial dysfunction in diabetic patients. However, the relationship between these factors remains unclear. We observed a chronological change in circulating adipocytokines and blood pressure levels with administration of oral hypoglycaemic agents in Type 2 diabetic (T2DM) subjects. METHODS: Thirty poorly controlled T2DM subjects (aged 60.1 +/- 1.5 years, 11 males and 19 females) were randomized into two groups: voglibose (initial dose 0.6 mg/day, increased to 0.9 mg/day) and pioglitazone (initial dose 15 mg/day, increased to 30 mg/day). RESULTS: Both treatment groups showed a similar improvement in glycaemic control. In pioglitazone-treated patients, circulating adiponectin levels were significantly increased from 4 weeks after the start of treatment, and until the end of the study at 12 weeks. Plasma tumour necrosis factor-alpha (TNF-alpha) levels were significantly decreased only at 12 weeks. In contrast, no significant changes in plasma adiponectin or TNF-alpha levels were observed in voglibose-treated patients. Plasma PAI-1 and leptin levels were not significantly changed at 12 weeks in either treatment group. Pioglitazone significantly decreased systolic and diastolic blood pressure levels at 12 weeks, but voglibose had no effect. CONCLUSION: In summary, pioglitazone caused an immediate increase in circulating adiponectin levels, followed by a reduction of TNF-alpha. The observed increase in circulating adiponectin could be related to decreases in both systolic and diastolic blood pressure.     

Plasma vascular endothelial growth factor in Japanese Type 2 diabetic patients with and without nephropathy

Aim: To determine whether plasma vascular endothelial growth factor (VEGF) level is elevated in Type 2 diabetic patients with an early stage of diabetic nephropathy. Methods: We studied 71 Japanese Type 2 diabetic patients with normal serum creatinine level (<100 μmol/l) (age 63.0 [60.3–65.6] years old, diabetes duration 15.6 [14.0–17.3] years, HbA1c 7.36% [7.06–7.66%], mean [95% confidence interval, CI]): normoalbuminuric patients (n=36); microalbuminuric patients (n=21); and proteinuric patients (n=14). Plasma VEGF concentration was measured by a quantitative sandwich enzyme immunoassay technique. Results: Plasma VEGF concentration was not related to the degree of albuminuria: normoalbuminuric patients (25 [13–95] ng/l, median [25th–75th percentile]); microalbuminuric patients (33 [15–120] ng/l); and proteinuric patients (54 [17–107] ng/l). Plasma VEGF level in patients with retinopathy (25 [15–95] ng/l, n=30) was not elevated as compared to those without retinopathy (53 [14–126] ng/l, n=34). Plasma VEGF tended to correlated negatively with diabetes duration (R's=−.217, P=.0690) and HbA1c (R's=−.221, P=.0647), whereas there was no correlation between plasma VEGF level and age, serum creatinine or urinary albumin to creatinine ratio (ACR) of the patients, respectively. Plasma VEGF level in the group of patients with HbA1c equal to or below the median (<7.2%) was significantly higher than that in the group of patients with HbA1c above the median (>7.2%) (P<.05). Conclusions: The results suggested that Type 2 diabetic patients with microalbuminuria and those with retinopathy are not necessarily associated with an elevation of circulating plasma VEGF concentration. Plausible association between plasma VEGF level and glycemic control remains to be seen.     

Microangiopathy is independently associated with presence, severity and composition of carotid atherosclerosis in type 2 diabetes

Background and aims

Common mechanisms for the development of micro- and macroangiopathic diabetic complications have been suggested. We aimed to cross-sectionally investigate strength and characteristics of the association between carotid atherosclerosis and microangiopathy in type 2 diabetic patients.

Methods and results

Common carotid artery intima-media thickness (cIMT), carotid plaque (CP) type and degree of stenosis were evaluated by ultrasound, along with the determination of anthropometric parameters, HbA1c, lipid profile, assessment of diabetic retinopathy and nephropathy, in 662 consecutive patients with type 2 diabetes mellitus (T2DM). Patients were divided according to high/low cIMT, presence/absence of CP and of retinopathy and nephropathy. Patients with CP were older, more prevalently males, past smokers, had longer diabetes duration, significantly lower HDL cholesterol and more prevalent ischemic heart disease (all p < 0.05) as compared to those with cIMT < 1 mm. Microangiopathies were more prevalent in patients with CP than in those without. At multivariate logistic regression, factors independently associated with the presence of CP were age, past smoke, HDL cholesterol, retinopathy and retinopathy plus nephropathy. A significant independent correlation of CP stenosis with stage of retinopathy and nephropathy was found. Finally, echolucent CPs were associated with a lower prevalence of proliferative retinopathy than CP containing calcium deposits.

Conclusion

In T2DM, retinopathy, alone or in combination with nephropathy, is independently associated to CP, and severity of microangiopathy correlates with severity of carotid atherosclerosis. These observations, together with the different prevalence of proliferative retinopathy according to CP types, point to possible common pathogenic mechanisms in micro- and macrovascular complications.     

血管内皮生长因子、血小板源性生长因子-BB与2型糖尿病患者血糖波动及微血管病变的关系

目的观察糖化血红蛋白（HbAlC）〈7．0％的2型糖尿病患者血糖波动与糖尿病微血管病变（视网膜病变、糖尿病肾病）及血清血管内皮生长因子（VEGF）、血小板源性生长因子-BB（PDGF—BB）水平之间的关系，探讨其在HbAlC达标患者中的相互影响机制。方法选取2010年10月至2012年8月在黑龙江省医院内分泌科就诊的2型糖尿病患者100例，其中男52例、女48例，年龄40～66岁。根据是否合并糖尿病微血管病变分为单纯2型糖尿病组[A组，n=30，男14例，女16例，年龄（50±11）岁]，糖尿病肾病组[B组，n=38，男20例，女18例，年龄（52±10）岁]和糖尿病视网膜病变组[C组，n=32，男18例，女14例，年龄（53±13）岁]。另以同期于黑龙江省医院进行体检的25名健康者为正常对照组[Con组，n=25，男12例，女13例，年龄（48±9）岁]。人院前糖尿病患者均使用药物治疗。所有参试者均测定空腹血糖浓度（FPG）、总胆固醇（TC）、甘油i酯（TG）、低密度脂蛋白胆同醇（LDL—C）、高密度脂蛋白胆固醇（HDL—C）、餐后2h血糖浓度（2hPG）、24h尿微量白蛋白（24h尿ALB）和HbAlc。应用动态血糖监测系统连续监测血糖3d，计算平均血糖（MBG）、平均血糖标准差（SDBG）、平均血糖波动幅度（MAGE）、日内最大血糖波动幅度（LAGE）、日间血糖平均绝对差（MODD）和曲线下面积（AUC）。采用酶联免疫吸附法分别检测血清中VEGF和PDGF—BB水平。计量资料组间比较采用t检验，多组间比较采用单因素方差分析，糖尿病微血管并发症的影响因素采用logistic回归分析，PDGF．BB、VEGF相关因素采用多元线性回归分析。结果（1）B组PDGF—BB水平高于A组和Con组[分别为（53±12）、（31±6）、（26±4）μg／ml，F=9．56，P〈0．05]；C组VEGF水平高于A组和Con组[分别为（217±57）、（105±12）、（74±10）μg／ml，F=8．13，P〈0．05]。（2）动态血糖监测指标B组与A组比较，SDBG、LAGF、MAGE、MODD、AUC明显升高（t=2．57、3．46、5．75、3．59、4．28，均P〈0．05），C组与A组比较，SDBG、LAGF、MAGE、MODD、AUC明显升高（t=3．29、3．77、5．38、4．54、3．16，均P〈0．05），而MBG在3组间的差异无统计学意义，均P〉0．05。（3）logistic回归分析显示PDGF-BB、VEGF及血糖波动是糖尿病微血管并发症独立危险因素。分别以PDGF-BB、VEGF为因变量，以血糖波动指标SDBG、LAGF、MAGE、MODD、AUC及2hPG为自变量，采用多元线性回归分析可能影响PDGF-BB、VEGF的相关因素，结果显示，MAGE、SDBG和2hPG对PDGF-BB、VEGF影响最大。结论2型糖尿病患者微血管病变的发生发展与血糖波动具有明显相关性，血糖波动可导致血清血管内皮生长因子和血小板源性生长因子-BB水平增高，从而参与糖尿病视网膜病变、糖尿病肾病等微血管病变的进展。     

Tumour necrosis factor alpha down-regulation parallels inflammatory regression in ulcerative colitis patients treated with infliximab

BACKGROUND: Treatment with the anti-tumour necrosis factor alpha monoclonal antibody infliximab has been shown to be effective in moderate-to-severe ulcerative colitis. However, its effect on the mucosal histopathological abnormalities of this disease is largely unknown. This study aimed to assess the immunohistological effect of infliximab in ulcerative colitis. METHODS: Nine patients with moderate-to-severe ulcerative colitis received infliximab (5mg/kg) at weeks 0, 2 and 6, respectively. Colonic biopsies were collected before therapy and at week 10, when the Mayo score (including the endoscopic subscore) was also assessed. Severity of inflammation was evaluated by histologic score and histomorphometry. Immunohistochemical staining with antibody against tumour necrosis factor alpha was performed on all biopsies and expressed as percentage of positive stromal cells/1000 counted (tumour necrosis factor alpha score). RESULTS: A profound down-regulation of mucosal tumour necrosis factor alpha occurred in all the six patients who achieved a clinical response, but not in the three who did not respond. Median tumour necrosis factor alpha score dropped from 44.8 (range 35-58.3) to 12.8 (range 5.3-15.3) in the responders (p=0.03), whilst it remained unchanged in the non-responders. Such effect was related with a dramatic regression of the median histologic score, which dropped from 2.7 (range 2-3) to 0.5 (range 0.0-1.5) in responder patients (p=0.002). This was related to a virtual disappearance of neutrophils in responders (r=0.72; p=0.002; Spearman's test), but not in those who did not improve. Tumour necrosis factor alpha score appeared to be correlated with the histologic, endoscopic and clinical activity. CONCLUSIONS: A profound tumour necrosis factor alpha down-regulation appears to be strictly associated with a dramatic regression of the inflammation in patients with moderate-to-severe ulcerative colitis treated with infliximab. Such immunohistochemical effect seems to be critical for a clinical and endoscopic response to therapy.     

Oxidative DNA damage in CD34+ myelodysplastic cells is associated with intracellular redox changes and elevated plasma tumour necrosis factor-α concentration

Ineffective haemopoiesis in the myelodysplastic syndromes (MDS) is mediated, at least in part, by apoptosis, though the mechanisms of apoptotic induction are unclear. Tumour necrosis factor-α (TNF-α) promotes apoptosis via intracellular oxygen free radical production, oxidation of DNA and proteins, and is increasingly implicated in the pathogenesis of MDS. Using single-cell gel electrophoresis, we have identified oxidized pyrimidine nucleotides in the progenitor-enriched bone marrow CD34⁺ compartment from MDS patients (P = 0.039), which are absent in both CD34^? MDS cells (P = 0.53) and also CD34⁺ cells from normal subjects (P = 0.55). MDS CD34⁺ blood cells also showed oxidized pyrimidine nucleotides compared with CD34^? cells (P = 0.029). Within normal subjects no differences were seen between CD34⁺ and CD34^? bone marrow cell compartments. CD34⁺ bone marrow cell oxidized pyrimidines were strongly associated with elevated plasma TNF-α and low bone marrow mononuclear cell glutathione concentrations (5/6 patients) and the inverse relationship was also found (3/4 patients). This data implies a role for intracellular oxygen free radical production, perhaps mediated by TNF-α, in the pathogenesis of ineffective haemopoiesis in MDS and provides a rationale for the bone marrow stimulatory effects of antioxidants such as Amifostine in MDS.     

Elevated serum TNF-alpha level as a link between endothelial dysfunction and insulin resistance in normotensive obese patients.

AIMS: The aim of the study was to analyse the role of tumour necrosis factor-alpha (TNF-alpha) in insulin resistance and endothelial dysfunction in patients with different types of obesity. PATIENTS AND METHODS: Fasting serum TNF-alpha immunoreactive concentration (enzyme-linked immunosorbent assay, ELISA) and bioactivity (L929 cell cytotoxicity assay), endothelin-1 and C-peptide levels (radioimmunoassay, RIA) were measured in 15 patients with android- and 13 patients with gynoid-type obesity and 15 lean healthy controls with normal glucose tolerance and blood pressure. RESULTS: Significantly (P<0.01) higher TNF-alpha concentration (8.92 +/- 0.44 pg/ml) and bioactivity (3.12 +/- 0.48 U/ml) were found in patients with android obesity as compared to patients with gynoid obesity (7.01 +/- 0.30 pg/ml, 0.97 +/- 0.11 U/ml) and to the lean controls (6.88 +/- 0.26 pg/ml, 0.88 +/- 0.08 U/ml). Serum endothelin-1 (5.38 +/- 0.30 pg/ml) and C-peptide levels (4.82 +/- 0.71 ng/ml) were also significantly higher (P < 0.01) in patients with android-type obesity than in controls (3.89 +/- 0.43 pg/ml, 1.46 +/- 0.25 ng/ml, respectively). In patients with gynoid-type obesity, only the C-peptide levels proved to be significantly higher (2.84 +/- 0.29 ng/ ml). Endothelin-1 levels, although were found to be slightly higher, did not differ statistically from in controls (4.56 +/- 0.31 pg/ml). There were significant positive linear correlations only in patients with android-type obesity between TNF-alpha, body mass index (BMI), serum endothelin-1 and C-peptide levels. CONCLUSIONS: TNF-alpha may be one of the factors contributing to insulin resistance and vascular dysfunction in patients with android obesity.     

YKL-40, a new biomarker of endothelial dysfunction, is independently associated with albuminuria in type 2 diabetic patients

The aim of this study was to examine the possible association between YKL-40, a new biomarker of endothelial dysfunction, and albuminuria in 180 type 2 diabetic patients. Multivariate logistic regression analyses demonstrated that serum YKL-40 level was a determinant of albuminuria independently of conventional risk factors.     

2型糖尿病患者血清胆红素水平与糖尿病足的相关性

目的 探讨2型糖尿病(T2DM)患者血清胆红素水平与糖尿病足的关系。方法 选取2009-2015年海南省第三人民医院收治的1 269例T2DM患者,根据糖尿病足的诊断标准分为糖尿病足组(578例)和非糖尿病足组(NDF组,691例),同时根据Wagner分级将糖尿病足组分为低级别组(40例,Wagner 0级或1级)、中级别组(425例,Wagner 2级或3级)、高级别组(113例,Wagner 4级或5级)。再将578例糖尿病足患者根据是否截肢分为非截肢组(446例)和截肢组(132例)。所有患者入院时检测血清总胆红素、直接胆红素(D-BIL)和间接胆红素(I-BIL)水平,以及白细胞计数、肌酐、收缩压、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、γ-谷氨酰转肽酶(GGT)、尿酸、总胆固醇、甘油三酯、高密度脂蛋白-胆固醇(HDL-C)、低密度脂蛋白-胆固醇(LDL-C)、HbA1c和血红蛋白。收集糖尿病足患者的Wagner分级和截肢手术资料。进行二元或有序多元logistic回归分析,以确定T2DM患者糖尿病足及截肢的危险因素。结果 与NDF组相比,糖尿病足组患者年龄、吸烟和饮酒患者的比例、大血管并发症患者的比例均较高(χ2=3.852~474.272,P均<0.05);白细胞计数、肌酐、收缩压水平升高(U=6.485、35.421、36.155,P均<0.05),总胆红素、D-BIL、I-BIL、ALT、AST、GGT、尿酸、总胆固醇、甘油三酯、HDL-C、LDL-C、HbA1c、血红蛋白和高脂血症患者的比例降低(U=3.145~68.119,P均<0.05)。血清I-BIL水平≥6.0 μmol/L与糖尿病足呈负相关(OR=0.751,95%CI:0.570~0.980,P<0.05)。血清总胆红素>10.0 μmol/L与Wagner评分较低有关(OR=0.506,95%CI:0.298~0.857,P<0.05),血清I-BIL≥6.0 μmol/L是Wagner评分较低的保护因素(OR=0.280, 95%CI:0.147~0.538,P<0.05)。总胆红素≥10.0 μmol/L是截肢的保护因素(OR=0.474,95%CI: 0.243~0.921,P<0.05)。结论 T2DM患者血清胆红素水平下降与糖尿病足的严重程度以及截肢事件独立相关。     

Detection of tumor necrosis factor-α in bone marrow plasma and peripheral blood plasma from patients with aplastic anemia

Plasma levels of interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) were determined in healthy individuals and patients with aplastic anemia (ApAn). IFN-γ was not detected in normal peripheral blood plasma (PBP) or bone marrow plasma (BMP) and was present in PBP from only 2 of 22 patients and in BMP from 1 of 14 patients and the levels were low (< 1.5 U/ml). Elevated levels of TNF-α were present in BMP and PBP from patients but not in control (healthy donor) PBP and BMP. Eleven of twenty-four patients had elevated levels of TNF-α in their PBP and 6 of 13 patients had detectable levels of TNF-α in their BMP. Only one of the 14 healthy control donors had detectable TNF-α and the level was very low (7 pg/ml), while 13 of the 27 ApAn patients had detectable TNF-α (P = .009, chi-square test). Not surprisingly, the centers of the distributions of TNF-α concentrations of the controls and ApAn patients differed significantly (P < .017 for control and patient PBP and P < .056 for control and patient BMP, Wilcoxon rank-sum test). Spontaneous production of IFN-γ and TNF-α by cultured bone marrow mononuclear cells was observed in four of seven patients but not in the six healthy controls (P = 0.026). Spontaneous production of IFN-γ and TNF-α by cultured peripheral blood mononuclear cells from patients and controls was however similar. Phytohemagglutinin (PHA)-induced production of IFN-γ and TNF-α by cultured mononuclear cells did not differ significantly between ApAn patients and normal controls. The significance of overproduction of TNF-α in the pathophysiology of ApAn is discussed. © 1994 Wiley-Liss, Inc.     

2型糖尿病微血管病变患者血清血小板反应蛋白-1水平的变化及临床意义

目的 探讨2型糖尿病T2DM微血管病变与血清血小板反应蛋白-1（TSP-1）的相关性。 方法 将176例受试者研究对象分为糖尿病合并有微血管病变组组（A组,n=58例）、无、未合并微血管病变组（B组,n=64例）和与正常对照组（C组,,n=54例）,检测所有研究对象血清TSP-1水平及相关临床指标,并计算胰岛素抵抗指数（HOMA-IR）、胰岛β细胞功能指数（HOMA-β）。 结果 A组及、B组的血清TSP-1水平均显著高于C组（P〈0.05）,A组的血清TSP-1水平显著高于B组（P〈0.05）。相关分析示,血清TSP-1水平与FBG、HbA1Cc、hs-C-RP呈正相关（P〈0.01）,与HOMA-β指数及FINSns呈负相关（P〈0.01）。多元线性逐步回归结果显示：,HbA1Cc、FPG、HOMA-β及FINSns是血清TSP-1水平的独立影响因素（P〈0.05）。 结论 TSP-1在2型糖尿病T2DM微血管病变患者血清中表达升高,其可能参与糖尿病微血管病变病理生理过程,检测血清TSP-1的水平对预测糖尿病微血管病变有一定的价值。     

Resistin polymorphisms are associated with cerebrovascular disease in Finnish Type 2 diabetic patients.

AIMS: Resistin is a hormone secreted by adipocytes and it is also expressed in monocytes. Resistin has been found to increase insulin resistance, a key feature in Type 2 diabetes. The aim of this study was to investigate whether resistin polymorphisms are associated with Type 2 diabetes and its clinical characteristics. METHODS: We studied the allele and genotype frequencies of the single-nucleotide polymorphisms (SNPs)-420 (C>G), +157 (T>C) and +299 (G>A) in the resistin gene in 258 Finnish Type 2 diabetics and 494 controls. RESULTS: These three markers were in significant linkage disequilibrium with each other. No significant (P<0.05) differences in the allele or genotype frequencies were observed between the study groups. Subjects with Type 2 diabetes showed a significant association between cerebrovascular disease and the SNPs-420 (P=0.004) and +299 (P=0.007), the G-G and A-A genotypes, respectively, had the highest frequencies. SNPs-420 (P=0.000) and +299 (P=0.002) in men and SNP+157 in men (P=0.005) and in women (P=0.019) showed significant association with higher mean blood glucose. The rare allele homozygotes also had the highest mean blood glucose values. We also observed associations between at least one of the SNPs and fasting blood glucose, glycosylated haemoglobin A1 (GHbA1), low-density lipoprotein (LDL) cholesterol and systolic and diastolic blood pressure. After correction for multiple comparisons, the association between the promoter variant SNP-420 and cerebrovascular disease in both genders and the associations between mean blood glucose and SNP-420 and SNP+299 in men remained significant. CONCLUSIONS: The results suggest that resistin may play a role in atherogenesis probably through increasing insulin resistance.     

Abnormal endothelial release of fibrinolytic activity and fibronectin in diabetic microangiopathy

Summary Endothelial cell function in Type 1 (insulin-dependent) diabetic patients, both with and without retinopathy, was assessed by measuring the plasma fibrinolytic activity and fibronectin after 10 min venous stasis induced by a sphygmomanometer cuff. After venous stasis, diabetic subjects with proliferative retinopathy had fibrinolytic responses (median 0.13 increasing to 0.26 U/ml) in the low normal range, which were significantly less (p< 0.005) than control subjects (0.17–0.68 U/ml) and diabetic patients with minimal retinopathy (0.16–0.68 U/ml; p<0.01). Plasma fibronectin levels were similar in the different groups, but after venous stasis, rose significantly in the diabetic patients, both in those with proliferative retinopathy (mean 317–399 g/ml; p<0.002) and without retinopathy (312–371 g/ml; p<0.05) but not in normal subjects (304–333 g/ml). These changes in fibrinolytic activity and fibronectin were independent of blood glucose, glycosylated haemoglobin, or indices of sensory or autonomic nerve function. These disturbances of endothelial function, together with known abnormalities of haemostatic variables and microvascular reflexes, might convert a usually temporary obstruction of capillary blood flow into a pathological capillary closure, and might contribute to the inexorable progression of advanced diabetic microangiopathy in spite of good diabetic control.     

Cardiovascular autonomic neuropathy associated with carotid atherosclerosis in Type 2 diabetic patients.

AIMS: To clarify if cardiovascular autonomic neuropathy is associated with carotid artery atherosclerotic plaques in Type 2 diabetic patients. METHODS: Cardiovascular autonomic nerve function was related to carotid artery ultrasound in 61 Type 2 diabetic patients 5-6 years after diagnosis of diabetes. RESULTS: Cardiovascular autonomic neuropathy [abnormal age corrected expiration/inspiration (E/I) ratio or acceleration index (AI)] was found in 13/61 (21%) patients. Patients with cardiovascular autonomic neuropathy showed increased degree of stenosis in the common carotid artery (24.6 +/- 13.2% vs. 14.7 +/- 9.2%; P = 0.014) and a tendency towards a higher plaque score (4.0 +/- 1.7 vs. 3.2 +/- 1.6; P = 0.064). Controlled for age, AI correlated inversely with degree of stenosis (r = -0.39; P = 0.005), plaque score (r = -0.39; P = 0.005), and mean (r = -0.33; P = 0.018) and maximum (r = -0.39; P = 0.004) intima-media thickness in the common carotid artery. In contrast, E/I ratio correlated only slightly with mean intima-media thickness in the common carotid artery (r = -0.28; P = 0.049). CONCLUSIONS: Cardiovascular autonomic neuropathy was associated with carotid atherosclerosis in Type 2 diabetic patients. Abnormal E/I ratios reflect efferent structural damage to parasympathetic nerves whereas abnormal AI reflects afferent autonomic dysfunction possibly due to impaired baroreceptor sensitivity secondary to carotid atherosclerosis.